(15), and three brackets (14) and
(7) Inspect each terminal stud for damaged
handwheel (19) from the front disk (12).
threads, insulation, or wingnuts. Replace
(7) Remove the three screws (13) and
a damaged terminal.
separate the handwheel from the brackets
(8) Inspect each rheostat for broken or worn
defective resistor wire, damaged or
lockwashers (33) and inside housing (4)
from the control contact ring (11). Place
control contact ring (and assembled part)
aside for later disassembly.
or defective rheostat.
(2) and bracket (3) from the inside housing
(10) Remove the screw (5), washers (6 and 7),
and clip (8) from the inside housing (4).
(1) Refer to figure 25 and install the controls
(11) Remove screw (38), nut (36) and
and instruments, model SECM.
(2) Refer to figure 25 and install the controls
control ring (11).
and instruments, model CMU-5, in a
(12) Remove the front disk (12), and attached
parts from the contact control ring (11).
(13) Remove two screws (20), washers (21),
insulator block (39) from the front disk
Ten-Range Switch and Field Rheostat
(14) Remove the five drive screws (18) and
a. Removal and Disassembly.
dial plate (17) from the front disk.
(15) Remove the two insulation plates (10)
(1) Remove the ten-range switch and field
from the contact rings (9).
(16) Remove the four spring clips (35) from the
control contact ring (11) and the two
contact rings (9). Remove the contact
rings (9) and electrical contacts (34) from
Match mark inside housing, control
the control contact ring.
contact ring, front disk, and dial plate
b. Cleaning, Inspection, and Repair.
identical location on reassembly.
(2) Remove the field rheostat from the ten-
(1) Remove dirt and grease from all non-
metallic parts with a clean, dry, lint-free
(3) Remove the setscrew (24, fig. 26) that
Clean metal parts in approved
secures the handwheel (23) to the
cleaning solvent and dry thoroughly.
variable resistor (31) and remove the
(4) Remove the four screws (25) that secure
the case (27) to the springs (30) and
remove the case. Remove dial (26) from
(5) Remove the two screws (28) and washers
(29) and remove the springs (30) from the
variable resistor (31).